Hull of special stabilized shape



July 14, 1964 E. OLlVOTTl 3,140,686

HULL OF SPECIAL STABILIZED SHAPE Filed April 10, 1961 v 2 Sheets-Sheet 1 um N 5 G K (D 7 INVENTOR.

ELIA OLIVOTTI BY [15A a) r/ A TTOHVE Y5 HULL. OF SPECIAL STABILIZED SHAPE Filed April 10, 1961 2 Sheets-Sheet 2 INVENTOR.

ELIA ouvo'rn By r United States Patent "ice Claims priority, application Italy Apr. 11, 1960 1 Claim. (Cl. 1149-56) This invention relates to hull shapes and refers more particularly to a specially shaped hull for boats and ships which enables them to travel through the water at high speed while at the same time, provides increased stability and seaworthiness.

It is well known that pulling boats in order to be swift at the pushing oars must be slender hulled and have a curved bottom. Further, the loading must be maintained on or near the center line. However, these boats are not well suited for use with sails because they heel too easily before the wind thereby being susceptible to easy capsizing.

On the other hand, the wide-bottomed boat is more suitable for use with sail. However, the wide-bottomed hull encounters more friction in the water and is thus less fit to be used with oars.

It is with the above-mentioned limitations in known hull designs that the present construction has been evolved and it is accordingly a primary object of the present invention to provide a boat and ship hull that is equally suited for use with oars, sail, or motor power.

It is another object of the present invention to provide a hull construction that couples excellent gliding characteristics with those of stability, safety and seaworthiness.

These and other objects of the present invention which will become apparent from the following specification and claim are achieved by the provision of a hull shape in which the dipped part (or underwater portion) has been designed in order to reduce as much as possible the friction losses generated in moving through the water. Above the waterline, the hull is widened out to form two hydro-dynamical side stabilizers which skim over the water only during the side heeling of the boat or ship.

The specific construction details of the present invention will be made more manifest in the following specification taken in conjunction with the drawings wherein:

FIGURE 1 is a side elevational view of a boat hull constructed in accordance with the principles of the present invention;

FIGURE 2 is a plan view of FIGURE 1;

FIGURE 3 is an end elevational view of the hull shown in FIGURE 1 as viewed from the front end;

FIGURE 4 is a side elevational view of another form of a hull constructed in accordance with the principles of the present invention and suited for use as a speed boat; and

FIGURE 5 is a plan view of the hull shape shown in FIGURE 4.

Referring now in greater detail to FIGURES 1 through 3 of the accompanying drawings, wherein like reference numerals indicate like parts, the keel K in the dipped or underwater body portion has a remarkable hydro-dynamical shape. It is thin and long to reduce resistance of the underwater body portion in passing through the water. Above the waterline GL the hull widens out at each side to form two side stabilizers ST, the stabilizers extending parallel to the water surface in normal floating position of the hull and further extending from stem to stern, which during heeling of the hull, skim over the water to provide a counter-balancing force of buoyancy in the hull. The stabilizers ST comprise in addition to the outer hull, an inner wall SD so that the stabilizer is in fact a water tight void serving as a flotation box extending all around the hull. In addition to the buoyancy factor imparted to the hull by the stabilizers, they provide a construction of considerable lightness and stoutness. It has been found that the stabilizers will keep the hull afloat even if the entire underwater body portion of the hull is full of water.

One of the advantages of this type of construction, as compared to that comomnly known, is the fact that when one side of a boat is pressed down, the hull pivots on its longitudinal axis and as soon as this heeling takes place, the counter-balancing effect of the stabilizers immediately provides resistance to further heeling, whereas in the prior art construction, the boat heels some times to a point dangerously approaching capsizing before the counterbalancing force of the hull itself acts to right it.

Thus, we see that a hull of the present construction increases seaworthiness and since the keel is very sharp and deeply dipped, a high order of speed can be achieved in a rough sea without flappings of the keel. Very large hulls can have a thin and deep keel laden with ballast.

Another advantage of the construction of the present invention stems from the fact that the use of side stabilizers allows for a wider beam and it follows that more room and useful space within the hull is available. In addition, the entire wall SD can be used as part of the seats S to provide arm rests or back rests for persons seated in the boat. Since the underwater body portion of the hull is thin and deeply dipped, the load placed in the boat can be centered well down in the underwater body portion, thus reducing top heaviness.

The above stated hull construction is applicable to boats of any size and used for any multitude of purposes. 'llie hull illustrated in FIGURES 1 through 3 is for a boat about 5 meters long with a beam of approximately 1.7 meters.

FIGURES 4 and 5 show another form of bull constructed in accordance with the principles of the present invention for use as a speed boat. In this case, the bottom of the underwater body is made flat instead of curved. In addition, the stabilizers also has a fiat bottom and they slant upwardly from a low point near the stern towards the stern. This form of construction is particularly adapted for use with speed boats since the stabilizers assist in the rearing of the hull at the start.

It should be apparent that the construction described above has been given by way of illustration and not by way of limitation and that it is subject to variations and modifications. All such variations and modifications are to be included within the scope of the present invention.

What is claimed is:

A boat hull comprising a hydro-dynamically shaped underwater body portion extending from stem to stern and having a sharp keel and curved sides extending outwardly of said keel, and an integral overwater portion Patented July '14, 1964 having two hydro-dynamic side stabilizers extending from stem to stern on both sides of said underwater body portion, each of said stabilizers having a substantially fiat and substantially horizontal undersurface located above the waterline and extending outwardly from one of said 5 curved sides, and a substantially vertical side extending above said undersurface and a convex surface joining said under-surface with said side, whereby in water said underwater portion has a cleaving effect While said over- 10 water portion has a planing effect.

References Cited in the file of this patent UNITED STATES PATENTS FOREIGN PATENTS Great Britain Sweden Jan. 12, France Mar. 15, 

